In his autobiography, Benjamin Franklin tells of a rival legislator with whom he was having trouble getting along. Franklin devised what may seem as a counterintuitive plan to win him over.

Knowing that this rival had a rare book in his library, Franklin sent him a message requesting that the legislator lend him the book for a few days. Franklin returned the book with a thank you note a week later. Subsequently, the man who up to this point never spoke to Franklin, treated him with great civility and they kindled a friendship for the rest of their lives.

The lesson from this story became known in the psychological literature as the Ben Franklin Effect. First studied in the 1960’s by Jon Jecker and David Landry, the Ben Franklin effect demonstrates that a benefactor who does a favor for another person is likely to increase positive feelings towards the person he is benefiting, even if the benefactor originally did not like the other person.

The hypothesized psychological concept underlying this phenomenon is cognitive dissonance. We tend to dislike having competing conceptions of ourselves in our minds so we generally try and synthesize perceived differences. On the one hand, it doesn’t make sense to help someone that I don’t like, yet on the other hand, I helped this person who I thought I didn’t like. Hence, subconsciously I resolve that it must be that I really do like the person.

If we pay close attention to the laws Moses repeats in Deuteronomy, we will notice discrepancies between the formulation in Deuteronomy and previous presentations. In this week's Torah portion the law regarding helping a fallen animal on the road states, “If you see your fellow’s donkey or ox fallen on the road, do not ignore it - you must help him raise it” (Deut 22:4). Yet in Parshat Mishpatim the law reads as follows: “When you see the donkey of your enemy lying under its burden and would refrain from raising it, you must nevertheless raise it with him” (Exodus 23:5). While there is more than one difference between the verses, the most glaring one that the commentators address is the switch from the animal belonging to one’s enemy (“sona’acha”) to belonging to one’s fellow (“achica”). Why the switch from enemy to friend?

Rabbi Meir Simcha of Dvinsk, in his commentary, Meshech Chochma, suggests a chronological answer. Something significant happened in between the presentation in Parshat Mishpatim where it says “enemy” and Parshat Ki Teitzei where it says “fellow,” namely, the sin of the golden calf. To make his point, Rabbi Meir Simcha first references the Talmud in Pesachim (113a), which is bothered by the use of the term “sona’acha” - enemy or hated one – used in in Parshat Mishpatim. Doesn’t the Torah in Parshat Kedoshim (Vayikra 19:17) prohibit us from hating each other?

The Talmud answers that there is an exception to the rule. One is allowed, and even perhaps obligated, to hate someone whom he sees has transgressed a commandment. In a powerful limitation of the application of this Talmud, Rabbi Meir Simcha argues that this is only true before the Children of Israel sinned with the golden calf. Afterwards, we all became spiritually flawed and limited. Only someone who is pure and virtuous, would be allowed to have a righteous indignation towards those that have sinned. After the sin of the golden calf, there is nobody who could reach such a status, hence everyone should be considered brethren. Therefore the verse in Parshat Ki Teitzei switches from the term “enemy” to “fellow,” because enemy is no longer a viable option.

Rabbeinu Bechaye suggests a different answer to the switch from enemy to friend. He writes that the Torah is hinting to a strategy as to how to transform someone from an enemy to a friend. If there is someone that you don’t like, and you go out of your way to help him, you will come to like him. By doing him a favor, you will become his friend. In other words, the switch of the words in the verses is hinting to the Ben Franklin effect.

If we would like to decrease the amount of strife and hatred in our lives, we would do well to internalize these messages. First, realize that there are limited acceptable justifications for hating someone. Second, if we do have strong negative feelings towards other people, consider doing them a favor. By acting kindly towards them, you can alter your own perceptions and enhance the relationship, transforming them from enemy to friend.